1. Field of the Invention
The present invention relates to an interchangeable lens camera and, more particularly, to a mount lock apparatus therefor.
2. Description of the Related Art
In a mount lock apparatus in a known interchangeable lens camera in which a photographing lens unit is interchangeably attached to a camera body through a bayonet mount, mount lock pins are provided on, and project from, an annular connecting surface of a front decorative member attached to a front surface of the camera body, so that when the mount lock pins are engaged with the photographing lens unit, no rotation or disengagement of the photographing lens unit takes place, as shown in Japanese Unexamined Patent Publication No. 10-90773. The mount lock apparatus is provided with an unlocking button which is operated to move the mount lock pins away from the connecting surface upon attachment or detachment of the photographing lens unit. The unlocking button is provided on a side surface of the front decorative member and is depressed in the optical axis direction to retract the mount lock pins in association therewith in the optical axis direction.
However, in recent cameras which have been miniaturized, the front decorative member cannot be reduced in size in order to preserve high compatibility with various kinds of photographing lens units. In accordance with miniaturization of the camera, the distance between a grip member which can be held by a user, provided on one side of the camera body and the unlocking button provided on the side surface of the front decorative member is reduced. Due to the reduced distance, a user tends to accidentally touch the unlocking button with his or her finger, thus leading to an unintentional operation of the unlocking button. In particular, in the unlocking button which is depressed in the optical axis direction as described above, as the operating direction of the unlocking button with his or her finger and the direction in which the user holds the camera with his or her fingers are identical, an unintentional operation tends to occur, thus resulting in a positional deviation or an accidental detachment of the photographing lens unit. Moreover, a miniaturization of a camera causes the problem of the unlocking button interfering with the user's fingers which hold the grip portion of the camera, so that the user may feel uncomfortable when holding the camera.